// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_
#define MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_

#include <stddef.h>
#include <stdint.h>

#include <string>
#include <vector>

#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/thread_checker.h"
#include "media/base/content_decryption_module.h"
#include "media/blink/new_session_cdm_result_promise.h"
#include "third_party/WebKit/public/platform/WebContentDecryptionModuleSession.h"
#include "third_party/WebKit/public/platform/WebString.h"

namespace media {

class CdmSessionAdapter;

class WebContentDecryptionModuleSessionImpl
    : public blink::WebContentDecryptionModuleSession {
public:
    WebContentDecryptionModuleSessionImpl(
        const scoped_refptr<CdmSessionAdapter>& adapter);
    ~WebContentDecryptionModuleSessionImpl() override;

    // blink::WebContentDecryptionModuleSession implementation.
    void setClientInterface(Client* client) override;
    blink::WebString sessionId() const override;

    void initializeNewSession(
        blink::WebEncryptedMediaInitDataType init_data_type,
        const unsigned char* initData,
        size_t initDataLength,
        blink::WebEncryptedMediaSessionType session_type,
        blink::WebContentDecryptionModuleResult result) override;
    void load(const blink::WebString& session_id,
        blink::WebContentDecryptionModuleResult result) override;
    void update(const uint8_t* response,
        size_t response_length,
        blink::WebContentDecryptionModuleResult result) override;
    void close(blink::WebContentDecryptionModuleResult result) override;
    void remove(blink::WebContentDecryptionModuleResult result) override;

    // Callbacks.
    void OnSessionMessage(ContentDecryptionModule::MessageType message_type,
        const std::vector<uint8_t>& message);
    void OnSessionKeysChange(bool has_additional_usable_key,
        CdmKeysInfo keys_info);
    void OnSessionExpirationUpdate(base::Time new_expiry_time);
    void OnSessionClosed();

private:
    // Called when a new session is created or loaded. |status| is set as
    // appropriate, depending on whether the session already exists or not.
    void OnSessionInitialized(const std::string& session_id,
        SessionInitStatus* status);

    scoped_refptr<CdmSessionAdapter> adapter_;

    // Non-owned pointer.
    Client* client_;

    // Session ID is the app visible ID for this session generated by the CDM.
    // This value is not set until the CDM resolves the initializeNewSession()
    // promise.
    std::string session_id_;

    // Keep track of whether the session has been closed or not. The session
    // may be closed as a result of an application calling close(), or the CDM
    // may close the session at any point.
    // https://w3c.github.io/encrypted-media/#session-closed
    // |has_close_been_called_| is used to keep track of whether close() has
    // been called or not. |is_closed_| is used to keep track of whether the
    // close event has been received or not.
    bool has_close_been_called_;
    bool is_closed_;

    base::ThreadChecker thread_checker_;
    // Since promises will live until they are fired, use a weak reference when
    // creating a promise in case this class disappears before the promise
    // actually fires.
    base::WeakPtrFactory<WebContentDecryptionModuleSessionImpl> weak_ptr_factory_;

    DISALLOW_COPY_AND_ASSIGN(WebContentDecryptionModuleSessionImpl);
};

} // namespace media

#endif // MEDIA_BLINK_WEBCONTENTDECRYPTIONMODULESESSION_IMPL_H_
